ceph: exclude setfilelock requests when calculating oldest tid

setfilelock requests can block for a long time, which can prevent
client from advancing its oldest tid.

Signed-off-by: Yan, Zheng <zyan@redhat.com>

diff --git a/fs/ceph/mds_client.c b/fs/ceph/mds_client.c
index 76eb144..69a36f4 100644 (file)
--- a/fs/ceph/mds_client.c
+++ b/fs/ceph/mds_client.c
@@ -628,6 +628,9 @@ static void __register_request(struct ceph_mds_client *mdsc,
        req->r_uid = current_fsuid();
        req->r_gid = current_fsgid();
 
+       if (mdsc->oldest_tid == 0 && req->r_op != CEPH_MDS_OP_SETFILELOCK)
+               mdsc->oldest_tid = req->r_tid;
+
        if (dir) {
                struct ceph_inode_info *ci = ceph_inode(dir);
 
@@ -643,6 +646,21 @@ static void __unregister_request(struct ceph_mds_client *mdsc,
                                 struct ceph_mds_request *req)
 {
        dout("__unregister_request %p tid %lld\n", req, req->r_tid);
+
+       if (req->r_tid == mdsc->oldest_tid) {
+               struct rb_node *p = rb_next(&req->r_node);
+               mdsc->oldest_tid = 0;
+               while (p) {
+                       struct ceph_mds_request *next_req =
+                               rb_entry(p, struct ceph_mds_request, r_node);
+                       if (next_req->r_op != CEPH_MDS_OP_SETFILELOCK) {
+                               mdsc->oldest_tid = next_req->r_tid;
+                               break;
+                       }
+                       p = rb_next(p);
+               }
+       }
+
        rb_erase(&req->r_node, &mdsc->request_tree);
        RB_CLEAR_NODE(&req->r_node);
 
@@ -1682,13 +1700,9 @@ static struct ceph_mds_request *__get_oldest_req(struct ceph_mds_client *mdsc)
                        struct ceph_mds_request, r_node);
 }
 
-static u64 __get_oldest_tid(struct ceph_mds_client *mdsc)
+static inline  u64 __get_oldest_tid(struct ceph_mds_client *mdsc)
 {
-       struct ceph_mds_request *req = __get_oldest_req(mdsc);
-
-       if (req)
-               return req->r_tid;
-       return 0;
+       return mdsc->oldest_tid;
 }
 
 /*
@@ -3378,6 +3392,7 @@ int ceph_mdsc_init(struct ceph_fs_client *fsc)
        INIT_LIST_HEAD(&mdsc->snap_empty);
        spin_lock_init(&mdsc->snap_empty_lock);
        mdsc->last_tid = 0;
+       mdsc->oldest_tid = 0;
        mdsc->request_tree = RB_ROOT;
        INIT_DELAYED_WORK(&mdsc->delayed_work, delayed_work);
        mdsc->last_renew_caps = jiffies;
@@ -3471,7 +3486,8 @@ restart:
                        nextreq = rb_entry(n, struct ceph_mds_request, r_node);
                else
                        nextreq = NULL;
-               if ((req->r_op & CEPH_MDS_OP_WRITE)) {
+               if (req->r_op != CEPH_MDS_OP_SETFILELOCK &&
+                   (req->r_op & CEPH_MDS_OP_WRITE)) {
                        /* write op */
                        ceph_mdsc_get_request(req);
                        if (nextreq)

diff --git a/fs/ceph/mds_client.h b/fs/ceph/mds_client.h
index 294fa23..2ef7999 100644 (file)
--- a/fs/ceph/mds_client.h
+++ b/fs/ceph/mds_client.h
@@ -296,6 +296,8 @@ struct ceph_mds_client {
        spinlock_t              snap_empty_lock;  /* protect snap_empty */
 
        u64                    last_tid;      /* most recent mds request */
+       u64                    oldest_tid;    /* oldest incomplete mds request,
+                                                excluding setfilelock requests */
        struct rb_root         request_tree;  /* pending mds requests */
        struct delayed_work    delayed_work;  /* delayed work */
        unsigned long    last_renew_caps;  /* last time we renewed our caps */